An electron beam processing apparatus such as an electron microscope or an electron beam exposure system requires high accuracy in electron beam control. For this reason, such an electron microscope or an electron beam exposure system is subjected to an inspection before performing observation or exposure using an electron beam as to whether an irradiation position, a shape, a current, and other characteristics of the electron beam match predetermined values. Then, the electron beam processing apparatus performs processing such as exposure or observation of a sample after undergoing adjustment of the electron beam by use of a result of the inspection.
There are known electron beam detectors for inspecting an electron beam, which are configured to detect the electron beam passed through an opening in a shield plate. Examples of such conventional technologies are disclosed by, for example, Japanese Laid-open Patent Publication No. H05-080158, Japanese Laid-open Patent Publication No. H09-293652, Japanese Laid-open Patent Publication No. 2001-118787, and Japanese Laid-open Patent Publication No. 2006-093579.
However, the conventional electron beam detectors have a problem that electron beam detection sensitivity varies largely depending on the irradiation position of an electron beam and thus the electron beam cannot be measured accurately.